Path: csiph.com!optima2.xanadu-bbs.net!xanadu-bbs.net!news.glorb.com!usenet.stanford.edu!not-for-mail From: Christian Neukirchen Newsgroups: gnu.bash.bug Subject: Bash does not exit on non-interactive "Bad substitution" errors Date: Tue, 04 Aug 2015 14:08:13 +0200 Lines: 27 Approved: bug-bash@gnu.org Message-ID: NNTP-Posting-Host: lists.gnu.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: usenet.stanford.edu 1438693340 23165 208.118.235.17 (4 Aug 2015 13:02:20 GMT) X-Complaints-To: action@cs.stanford.edu To: bug-bash@gnu.org Envelope-to: bug-bash@gnu.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:subject:date:message-id:user-agent:mime-version :content-type; bh=fQZYcJJYGCq6PGfY3c/mDzs6qFdFj82xOruUirxZT3U=; b=vfovPraSfKd2/aUONGTGrffX8tslnCfTPDDKDoqdHl8UrSyARqVg3QEGWd0am8O2oA BaUfMbJJAlkKlE/e4q87MW2sgTrMcqcUhRkoulPaDc5F+H0FBWnt5s2F3Q8MWkziAWAg RbhD5C4L9V6jG2mkaaoNz4sqNhDxugHQiYHlLieXbhBN6zoOwzqFegHupYyL/WzfU7D+ zuq5ruRJ57hLm/RjuOckocoQR1VYFkiGeHb4ihB/sjtB5FJ9jxWMtPhyUCw3Tx7mc4QW yOa6/+USubnID5tK5dw68qtlpQKWLwOqyREjSQI75hFPOSc5IG0motatyRJ0D8Znpw/v j49g== X-Received: by 10.195.11.74 with SMTP id eg10mr7169780wjd.33.1438690094530; Tue, 04 Aug 2015 05:08:14 -0700 (PDT) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) X-detected-operating-system: by eggs.gnu.org: Error: Malformed IPv6 address (bad octet value). X-Received-From: 2a00:1450:400c:c05::22e X-Mailman-Approved-At: Tue, 04 Aug 2015 09:02:19 -0400 X-BeenThere: bug-bash@gnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Bug reports for the GNU Bourne Again SHell List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Xref: csiph.com gnu.bash.bug:11292 Hi, I noticed that the following script keeps executing (and outputs "oops") in Bash 4.3.39(1)-release and 2.05b.13(1)-release, in difference to dash-0.5.8, mksh-R51, busybox sh v1.23.2, ksh-2012.08.01, and zsh-5.0.8: echo ${x!y} echo oops According to IEEE Std 1003.1, 2.8.1 Consequences of Shell Errors "An expansion error is one that occurs when the shell expansions defined in wordexp are carried out (for example, "${x!y}", because '!' is not a valid operator)" and should result in "Shall exit" from a non-interactive script. In particular, this also happens when the expansion error occurs in a line consisting of an "exec"-statement, where evaluation usually *never* continues (e.g. bash correctly exits when the command is not found). I think to avoid further damage due to badly set variables, bash should exit in this case as well. Thanks, -- Christian Neukirchen http://chneukirchen.org